I found the following users who may fit your language exchange criteria:

Username	Date	Post Link	Relevance	Offered Matches	Sought Matches
u/decent_pressure_9067	2022-02-03	Post	`11`	English, Russian (Native), Ukrainian (Native)	English
u/iknowtheguywhoknow	2022-02-18	Post	`11`	English, Russian, Ukrainian	English
u/annualput3782	2022-03-13	Post	`11`	English, Japanese, Russian (Native)	English
u/silverraibowcat	2022-03-15	Post	`9`	English (B1), Japanese (A2), Russian (Native)	---
u/indigostrength	2022-04-09	Post	`9`	English, Russian, Ukrainian	---

Please feel free to comment on the above posts to get in contact with their authors.